This core will provide computer software and hardware support for the four research projects and for the two other cores. Projects 1, 2, and 3 require the augmentation of the existing treatment planning system, U- MPlan, to incorporate fully conformal 3-D treatment techniques as they are developed within the projects. Augmenting U-MPlan with the knowledge of these new techniques will facilitate further study of these techniques in a routine clinical setting. Projects 2 and 3 require enhancement of clinical computer software such as the CCRS (Computer-Controlled Radiotherapy System) in order to help measure the efficacy of methods explored within those projects. This core also provides Project 4 with any treatment planning tools needed to study the effects of tumor dose escalation. The treatment planning/dosimetry core will be supported with software tools necessary for analysis of gathered data, and with integration tools needed to exchange data between research projects and clinical software systems. This core will provide, to all projects and cores, a stable, well-maintained computing environment, including such basic elements as a programming staff well versed in software design and test methodology, a comprehensive and reliable computer network, archives of research data, and the personnel and tools necessary for management and acquisition of computer resources. In addition, this core will provide hardware and software support for the commercial megavoltage imager and for the flat-panel composite megavoltage and diagnostic imagers to be used with projects 2, 3, and 4. In project 2, a megavoltage imager will provide verification of field shape defined by the multileaf collimators. In project 3 and 4, a megavoltage and diagnostic imager will be used in verification of the treatment setup. This core includes the purchase of commercial imager and support for the installation, periodic calibration and quality assurance, and routine operation of the imagers during the course of the research. Finally, software for the manipulation, processing, and archiving of image data from the commercial megavoltage imager will be provided.